Wednesday 7 April 2010 13.59 EDT
First published on Wednesday 7 April 2010 13.59 EDT

Martina Navratilova, who announced today that she has been diagnosed with breast cancer, described the day she found out as "my own personal 9/11".

The nine-time Wimbledon singles champion said she cried when a biopsy came back positive on 24 February after a routine mammogram.

"It knocked me on my ass, really," Navratilova, 53, told People magazine. "I feel so in control of my life and my body, and then this comes and it's completely out of my hands."

Doctors told her she has a non-invasive form of the cancer called ductal carcinoma in situ, or DCIS, which means the cancer is confined to the milk ducts and has not spread to the surrounding tissue.

A friend of Navratilova, Dr Mindy Nagle, said: "It was the best case scenario you could imagine for detecting breast cancer."

The tennis star, who was named one of the top 40 athletes of all time by Sports Illustrated, had a lumpectomy and will undergo radiation therapy in May.

Navratilova, who is a health and fitness ambassador for AARP, a US campaign group for the over-50s, described herself as very lucky to have had the cancer picked up so early.

However, she admitted she had "let it slide" by going four years between mammograms, and said: "Another year and I could have been in big trouble."

In a statement, issued through AARP, she cited her toughest tennis opponents – Chris Evert, Steffi Graf, Monica Seles and, in doubles, the Williams sisters – but said battling cancer had been tougher. She said: "The day I was told I had breast cancer was my own personal 9/11. I was completely shocked and the news knocked the wind out of me.

"This is a huge wake-up call for me and just goes to show no matter how much you watch what you eat or exercise you just never know.

"Here I am, the health and fitness ambassador for AARP, speaking to millions each month about staying healthy and I let my annual check-ups fall to the bottom of my to-do list. It's not all about eating right and exercising. Preventative steps can make just as much, or in some cases more, of a difference. Getting my mammogram literally saved my life."

She urged people to take responsibility, get recommended screenings and to stay healthy. Navratilova still regularly plays tennis and ice hockey and competes in triathlons. Czech-born Navratilova became a US citizen in 1981.

DCIS, sometimes called pre-invasive or non-invasive breast cancer, is a form of the disease in which the cells inside some of the milk ducts have started to turn into cancer cells.

Because they are inside the ducts there is little chance they can spread to the rest of the breast tissue or elsewhere in the body. However, if not treated, over time it may become invasive.

The recommended treatment for DCIS used to be a mastectomy, but recent research by the British Journal of Cancer found that, in the UK, over 60% of women who have DCIS do not require a mastectomy. Most surgeons recommend a lumpectomy, with radiotherapy to kill off any unhealthy cells left behind.

According to Cancer Research UK, if someone is diagnosed with DCIS and treated they will almost certainly be cured of the disease.

Stephen Duffy, Cancer Research UK's professor of cancer screening at Queen Mary, University of London, said: "We are very sorry to hear of Martina's diagnosis and our thoughts are with her and her family at this time."

"Breast screening can catch cancer at an early stage when it is often easier to treat, so we would encourage women to go when invited. As well as attending screening, it's important that all women are breast aware and go to their doctor if they notice any unusual changes to their breasts."

Raising awareness

High-profile women with breast cancer have helped remove the stigma of the disease and encouraged women to have regular screenings. Kylie Minogue became an inspirational figure to many women after going public in 2005.

When her illness forced her to cancel a cancer charity ball, she sent a defiant message: "I am a cancer patient. I aim to be a cancer survivor."

Kylie, 41, who was given the all-clear in 2006, has helped to raise awareness of the disease and how to spot it.

Other high-profile women who have been diagnosed include singer Anastacia, 41, in 2003. She created The Anastacia Fund, an organisation that helps raise awareness about the importance of mammograms to women under 40.

Rock star Sheryl Crow, 45, who was diagnosed with early stage breast cancer in 2006 after a routine mammogram, also campaigns on the issue.

Actor Lynn Redgrave, 64, had breast cancer in 2002. Her book, Journal: A Mother and Daughter's Recovery from Breast Cancer written with her daughter, Annabel Clark, records how the treatment "set me free".